About Petra Johanne:
Edit 26 Sep 2013:
Details and documentation removed due to lack of response from the starter of the thread
August and Petra had two children:
Willie’s death record from 1916 links him to parents August and Petra.
His mother Johannah Peterson lives (1916) in New York with three children (girls). No mentioning of a husband (which should be Conrad).
There is a family in NY that may fit (established ca. 1903), but I’m not sure.https://familysearch.org/pal:/MM9.1.1/MK96-YSBhttps://familysearch.org/pal:/MM9.1.1/M5QH-ZDL
After all this doesn’t tell us much about Conrad Petersen (except that he maybe was born 1778-79 and that he shows up in NY shortly after 1900).